The
Doomworld Forums have an interesting follow-up to the fact that DOOM 3
made use of a "zfail" method of rendering shadows that is patented
by Creative Labs (thanks Ant). Recalling this, they asked id's John Carmack
how this might impact plans to release the DOOM 3 source code under the GPL at a
future date. Sure enough, this situation could potentially result in patent
infringement:

When we release the code (no date set), anyone that uses it
would potentially be infringing. There are workarounds at a modest performance
cost.

Oh my, Derek Smart to the rescue =P I can't wait to read the vitriol that will more than likely spew in 3, 2, 1...

If you have to ask who wants to play with Doom 3 source code then you obviously do not get it. Is it really that terrible that someone might want to take a look and learn from one of the greatest coders of the last 20 years? Is there not worth in peeking inside the black box? Like it or not, John Carmack has had a major influence over the gaming industry, certainly more than yourself.

I can't imagine anyone wanting to use that zfail method nowadays anyway when there are so many workarounds. Machines are far faster now and more capable than when Doom3 was released. So the performance drop is negligible.

Then again, why would be pissing around with the Doom 3 source anyway?

Game developers are just human beings who happen to make games for a living. If you want to hold us up to higher standards of conduct, then go ahead...but don't be surprised if we don't uphold them

I think id/johnc can just remove the offending code and the community would be plenty happy to write new shadow code. No problem.

Actually id doesn't have to remove anything for it to stay in the legal clear. Programmers who develop with the GPL'd Doom 3 source would simply have a choice to make. Pay a royalty or reach some agreement themselves with Creative Labs or write a work-around.

As a method of doing volume shadows zfail is well-known among graphics programmers, and Creative in no way invented it - they just got to the patent office first. It is described in numerous articles and books, not one of which says "btw if you use this you will have to pay the 'tards at Creative".

Actually, at the time of discovery by Creative, zfail was unknown amongst graphics programmers. Stencil shadows were a well known technique, but eliminating artefacts of shadow volume intersection with the near plane was either ignored or solved analytically by clipping the shadow volume against the near plane and patching up the holes.

Yeah - but the real question is, should they be able to patent what amounts to an algorithm? Especially one that Carmack came up with independently. The zfail method is also known as "Carmack's Reverse".

As a method of doing volume shadows zfail is well-known among graphics programmers, and Creative in no way invented it - they just got to the patent office first. It is described in numerous articles and books, not one of which says "btw if you use this you will have to pay the 'tards at Creative".

JUST SAY NO TO ALGORITHM PATENTS! It's like saying someone can patent long division.

I haven't owned a Creative Labs card since the nForce motheborads first came out... and even before the nForce motherboards, my sound cards were "Windows 98 era" purchases.

Sound Blasters were great in the DOS era. In the Windows 9.x era they totally sucked because, as others have point out, buggy and bloated drivers.

I'm not dissing their hardware engineering, nor their innovations in audio technology. But their drivers have caused many a system crash. Granted, since 2000 / XP is way better at handling crashes than 9.x, the issues got better, but they still suck because of the bloat, IMO.

As someone else said, as soon as on-board audio got "good enough", Creative Labs pretty much became irrelevant. There is zero justification (IMO) to spend an extra $100-$200 on a device with crap drivers that might gain an extra 3% fps in a game... especially when most people don't run more than 2 speakers. And now with Shitsta... you lose some of the features (Although I think they came up with a work around).

If I were to spend the cash on a sound card today... I'd probably buy one of those new ASUS things. But I really can't see the justification over on-board... even with 5+ speakers plugged in... other than a couple of extra FPS. It's just not worth it to me, I guess.

Personally the engine used in Doom3 IMO isnt really that impressive, shit I like the Doom2 engine better.

As a game, I felt Doom 3 was horrible. It was beyond stale, some of the monsters were quite lame, it was too dark (light-wise), and the peek-a-boo thing was done WAY too much. The PDAs were a decent touch, a throw-back to things like System Shock 2 and Aliens vs Predator 2 (I never played the originals, so sue me), but for the most part it was like playing a game from the 1990's with fancy graphics.

That being said, you can't compare the two engines. the D3 engine was decades ahead of the D1 and D2 engine.

However, from what I recall, the D3 engine was kind of a hog. Other engines could render equal or better graphics in larger environments and require fewer resources. Far Cry and Half-Life 2 are some examples.

This comment was edited on Apr 8, 2009, 08:46.

"Space. It seems to go on and on forever. But then you get to the end and a gorilla starts throwing barrels at you." -Fry, Futurama

Well I still play Doom2 online, so yes I do like it better than Doom3 Obviously this is a very subjective opinion, but even objectively the Doom3 engine isnt really that impressive when compared to its counterparts like Source for example.

The graphics are admitedly impressive but, the physics felt especially convulted, jumping and moving around in every single game to use that engine somehow "felt" wrong. Bah Im being subjective again....

Personally the engine used in Doom3 IMO isnt really that impressive, shit I like the Doom2 engine better.

I realize you were probably going for hyperbole here, but really? Doom 2 being released back in 1994, and using the same engine that Doom 1 used. You actually think that's better than the Doom 3 engine?

I dont see what the big deal is, id just doesnt have to release the source code. Or if they do they can just implement a workaround. Personally the engine used in Doom3 IMO isnt really that impressive, shit I like the Doom2 engine better.

But yeah the fact that Creative would patent a graphics function, when they arent even in the graphics business is well a testament to human greed, and the fact that the patent system needs an overhaul.

By the way, I've found the cure for all cancers, but I'm not in the business of curing cancer, so I'm just going to patent it and wait until someone else figures it out and jump all over them, demanding that they pay me for my inventions that they didn't even know I had. It doesn't matter that they figured it out entirely independent of my knowledge, I own the patent!